Means for controlling the tension of coils or rolls of flexible material



March 15, 1932. A. s. F. G. RICHARDSON ET AL 1,849,383

MEANS FOR CONTROLLING THE TENSION OF COILS OR ROLLS OF FLEXIBLE MATERIAL 4 She ets-Sheet Filed May 20, 1930 /NVN7'0RS MW, 0. 2.97-

WA' LM BY ATTORNEYS March 15, 1932. A. B. F. G. RICHARDSONET AL 9,

MEANS FOR CONTROLLING THE] TENSION OF COILS OR ROLLS OF FLEXIBLE MATERIAL Filed May 20, 1930' 4 Sheets-Sheet March 15, 1932.

A. B. YF. G. RICHARDSON ET AL MEANS FOR CONTROLLING THE TENSION OF COILS OR ROLLS OF FLEXIBLE MATERIAL Filed May 20, 1930 4 Sheets-Sheet 3 4 M 4W4; Mal;

w fi J 3 f 8 l 3 Y 1 March 15, 1932. 1,849,383 MEANS FOR CONTROLLING THE TENSION 0F COILS OR ROLLS OF FLEXIBLE MATERIAL A. B. F. G. RICHARDSON ET AL I Filed May 20, 1930 4 Sheets-Sheet 4 m ME Patented Mar. 15, 1932 UNITED PATENT ea-I E} m'rnrua BBUCEFRASER GILLESPIE 1316mm Ann ARTHUR SPENCER} 0171 BELVEDEBE, E v

mums r03. comaoLmNe THE rmvsroiwor coILs oanoLLs or FLEXIB E MATERIAL Application filed May 20,1930, Serial "1T0. 453,891, and iii Great Britain- May 28,1929.

This invention deals with arrangements for controlling thetension on flexiblematerial, for instance strips of paper or lengths of fabric, which are being drawn from a .coil or roll. In such casesthe tension is com- 'monly determined by the value of a frictional retarding efi'ect applied to the coilor its carrier, and it is often desirable that the tension on the material should'remain approximately constant. Since the radius at which the material is drawn oil from the coil will vary continuously it is necessary to cause the momentof the frictional restraint to vary continuously from its maximum value downwards as the size of the coil decreases in order that a constant tension may be produced in the material. Arrangements for effecting such variation in the value of the moment of the frictionalrestraint applied to the coil'or its holder in cases where the axis about which the coil rotates is stationary in space are known. These arrangements comprise a reduction gearing driven by the coil holder and driving a member, the movement of which varies the pressure exerted byaspring on a brake acting upon the coil holder. Known devices of this type have been employed, for instance, in connection with web printing machines where it is desirable that the tension on the web of paper being withdrawn from the reel should be maintained approximately constant. I V i In accordance with the present invention we produce an arrangement of this general type, for coordinating the value of the frictional retarding force applied by a spring to a coil with the number of revolutions made by the coil, in a form suitable for controlling the tension when the axes about which the coils rotate are themselves rotatin or" otherwise moving rapidly in space. 1 T ese conditions apply to coils of paper tape/or other material carried on the rotating head of a lapping machine such as is used for insulating an electric cable. To provide an arrangement for'the purpose indicated wehave, according to this invention, produced .a tension control mechanism which is closelyassociated with the coil holder'so that the two form asingle unit. a

I order that thisinvention maybe more clearly understood three constructlons given by way of example will be described with reference to the accompanying drawings whereln V ig. l is an elevation with one half in section of a mechanism, embodyin "the'invention, to control the tension in flexfiilematerial which is being withdrawn from two coils.

Fig. Qis an end View in the direction of the arrow X, ofthe device shown in Fig. 1 but'having the locking nut and part of the handnut removed. I f i Fig. 3 is a sectional elevation of an alternative form of gearing which may be used in place ofthe gearing described in conjunction with Figsil and 2.

Fig.4- is an end'viewin'the direction of the arrow Y of Fig. 3 but with the cover of the gear box removed.

Fig. 5 is a sectional elevation of. another form of construction of. the tension controlling mechanism for two coils in-which the movements of both members controlling the elongation. of the springs are transmitted from alcoil holder by only one set of reduction gearing v Fig. 6 is was, of Fig. 5a the areas moved.

ticularly to Figs. 1 and 2, the shaftll carryingthe complete mechanism is fixed, for example, to the rotating head of. a lapping machine by means of the screw threaded end 2 and the locknut 3. This shaft l-hasfazflat surface 4' throughouta substantial part of its length.- A metal 'disc- 5, linedon'each face with a'friction'liningfi, is slotted-so that it may he slipped into position on the shaft 1, the sides .of-the slot in the metal disc sliding into grooves 7 cut in the shaft 1 and theend of the slot fitting the fiat 4 on theshaft. I The disc 'is' thus prevented from rotating and from moving axially along the shaft. Two

grooves are cut, one on each face of the disc face of the coil 9 remote from" the friction disc isa disc 11 which is fixed to the collar 12. The collar 12 is screwed on to the hub and locked in any desired position by means of theclamping'screw 13. 'The coil is gripped between the discs 11 and lwhen pressure in the direction of the latter-is exerted on the hub by a helical spring 15, partly contained in-a deep annular recess in thehub 10. The hub and disc .14 are both free torotate about the shaft 1. V

One ormore distance washers 16, each having a'device to prevent any angular movement between it and the disc 14, may be inserted between the. latter and the hub 10 to enable the coil holder to be readily adapted to carry coils of various widths without resetting the collar 12.

r The outer end of thehelical spring 15 presses against a face of a rotating member .17. The member 17, driven by the coil holder hub through a claw coupling 18, is per mitted to have a certain amount of axial movement along the shaft 1 whilst being driven. The face of'the member 17 remote from the spring 15 is recessed to receive a friction lining 19 attached to it bymeans of rivets. The pressure of the spring causes the outer face of the lining to press against the face of a member 20, which is preventedfrom' rotating byits, engagement with .the flat 4, but whieh'may slide axially along the shaft 1. Under pressure of the spring the member 20 tends to move axially away from the spring but is prevented from doing soby aninternally screwed collar or nut 21 (screwed on the end 22 of the shaft 1) of which the inner face fits in a recess in the adjacent face of the member 20.

It is clear that an axial movement of the nut 21, produced by its rotation onthe shaft 1,'away from the nut 10 will allow the helical spring 15 to elongate, thus reducing the pressure between the friction lining 19 and the sliding member 20 and the pressure between the disc 14 and the friction lining 6, and hence the retarding moment on the coil holder. To ensure that the retarding moment on the coil holder shall decrease as the diameter of the coil decreases it is merely necessary to corelatethe rotary motion on the coil holder. toth'at of the nut :21 through a suitable reduc tion gearing.

Referring now to Figs. 1 and 2 only, which illustrate one means of effecting this co-rela tion, the member 20 has two brackets 80 which carry spindles 23 and 2 1. A worm wheel 25 on the spindle 23 is driven by a worm. 26 cut on the periphery of the member 17 and drives, by means of the pinion 27 and an engaging pinion 28 on the spindle 24, a

ber 20. The nut 21 has an outer concentric part 32 which slides axially over the inner part 21, but which is prevented from rotatingrelative to it by means ofa feather 33,

"fitting inthe keyway34. The face of the outer part 32 which is adjacent to the worm wheel 29 has a number of projecting dowel pins 35 which are maintained in engagement with holes 86 on the wheel 29 by means of a locking. nut 37 screwed on to the end of the nut 21. The nut is caused to rotate and to move axially whilst the above engagement is maintained. When it is desired to insert new coils the locking nut is unscrewed suf ficiently'to permit the outer concentric part 8'2toslide clear of the worm wheel and allow both outer and inner parts of the nut together with the members 20 and 17, to be easily withdrawn from I and replaced on the shaft 1. After these operations have been carried out the nut 21 is reset to provide the initial value of friction.

In the complete mechanism shown in -Figs. .1 and 2 it isarranged that each of the nuts 21 shall be driven by the coil holder adjacent to it through its own gearing so that each nut moves axially away from the middle of the shaft as the material is unwound from the coil. This isdone by making one of the worms 26 left handed and the otherright handed as shown, but the same effect may be obtained by having one of the worms 30'left handed andrthe. other right handed or by'having one end vof theshaft, and thetwo part nut fitting it, screwed with a-left handed thread, thefother end and its nut being screwed with aright handed thread. In the holders'rotate in the same dicarrying a spring controlle'd pawl l-l anda pair of links 4-2, is fitted in the forked arm 39. The other ends of the links ,-.are pivotalabove arrangement it should beunderstood 1y anchored to the spindle 43supported at 'one end in a bearing in the coveri 44,*and at the other end in a bearing 45 attached to-the 'wheel 48 gears with a ring of internal teeth 50 attached to the flange 51 of the nut-21, which is not built up of two concentric parts as shown in Fig. 1. To maintain the gearing in "correct engagement; the sliding member 20 is axially anchored to thenut 21 by the plate 52 attached to the latter and running in a groove cut in the periphery of the hub of the former, and the eccentric strap is axially anchored to the sliding member 20 by means of a rib 53 on the outside of the strap, made concentric with the shaft 1 which runs between a face 54 of the member 20 and an inner face of the cover 44. The cover is held in position and attached to the member 20 by three distance bolts 55. The rotation of the coil holder hub is thus made, through the agency of the eccentric strap, and ratchet gear described, to produce a slow rotation of the nut 21. i

The spindle 40 to which is fixed the pawl 41, is extended through the cover 44 to terminate in a small disc 56. By means of this disc the pawl may be held out of engagement with the ratchet wheel to facilitate the removal from the shaft of the members 20, 21,

with its nut are screwed with a right handed thread.

In the tension controlling deviceshown in Figs. 5 and 6 the coil" holders are axially maintained in position by two ball thrust bearings 57 and 58 which are carried on a sleeve 59 and held in position by rings 60.

The sleeve 59 is positioned on theshaft 1, and prevented from rotating on it, by the slotted disc 61. The coil holder hub shown on the right hand side in Fig. 5 is in this case built up of an inner part 10 and an outer concentric part 62 having a screwed collar 12 on each side to grip the coil 9. The inner part 10 is free to rotate about the sleeve 59, contains a deep annular recess to receive the spring 15, and has its aws of the coupling 18 situate on its flange part. The thrust due to the spring on this member 10 is taken up by the bearing 58. The outerportion 62 fits oversthe inner The rotating member 17 which is on theright hand side of the hub62, which is carriedby it and driven by it through the coupling 18",

has a friction lining 19 which presses against the sliding member 20. This member20. carries a casing 63 which is split so thatit may either be closed to grip the member-20- (which 1 is, the normal working condition) by :tight- 1 ening the screw 64 or be allowed". to rotate about the said member; the 'set screw 64 being so placed that part of it fits into a groove'cut in the peripheryof the member 20am prevents aXial movement between the casing and the sliding member.

transferred through the casing 63 to the nut p e5 The pressure on the sliding member 20 is 21 controlling the elongation of thespring.

The form of gearing described in conjuncr tion with Figs. 1 and 2 is employed to transniit the motion of the driven member 17 to the wheel} 29,; but in this case the brackets carrying the spindles 23 and 24 areintegralwith the casing 63 and the worm withthenut21. i

The; movement of the. nut 21 directlyfcontrols the-braking-force on the coil holder adj acent to it and also controlsthebraking force on the other coil bymeans of the mechanism wheel 29 integral described below. An, annular disc .65 'is secured to the outer end of thenu t 21 by the nut 71 and is caused to rotate by projections on its'inner face engaging with slots in the -end of the nut 21. These projections are extended radially to. engage with grooves in the outside of the 'nut66 which is disposed .on the screwed end of the rod 67. v This rod 67 passes centrallythrough the shaft 1 and is'secured to theslidi'ng member 68 by the .pin 69. 0 The thrujst-onthe nut 66. is taken up bythe bearing 70. i i i If the two coils arethe'samesize and ifthe material from eachv is withdrawn-atthe same rate. then itfwillusually be desirable to reduce the-braking effect oneachcoil at the same rate. This may be conveniently performed y by making: the pitch of the nut 66 equal to that f of thenut 21; then the rotation of the nut 66, V

driven by thenut 21, allows the rod 67 t0 travelto the left at the same rateas the nut 21 trav-elsto the, right, and both springs are allowed toelongate at the same rateto reduce the frictionalmoment onthe coilholders as the materials are withdrawnfromsthe coils. To facilitate the withdrawal from and replacement on the shaft 1 of the coil holders, and the re-setting of the springs in their initialposition, the screw .64 is slackened sufficiently to permittheworin wheel 29. to rotate the casing'63 as, thcnut, 21 isnnscrewedfrom r the end of the shaft, the rotation of the worm sion on flexible material being withdrawn 26 and the coil holder hub is then avoided.

It is to be understood that the transmission gears described above in considerable detail 7 have only been set out by way ofexample, andnot With the object of indicating that the invention is restricted thereto. 7 v v What we claimras our invention and desire to secure by Letters Patent is V 1. An arrangement for controlling the tenfrom a coil comprising a rotary coil holder, a brake acting on said holder, a spring exert- -1ngaforceon the brake, a screw threaded .member and a nut worklng thereon and conmember and a nut working thereon and controlling said spring, a worm connected with the coilholder, a worm wheel co-axial with said worm and connected with said nut, a pair of parallel shafts, a pair of pinions coupling worm on the other shaft driving the worm 'wheel connected with the nut.

3. An arrangement for controlling the tension on flexible material being Withdrawn from a coil comprising a supporting member, a coil holder supported upon and adapted to be rotated about the axis of said supporting member, vmeans supported on the said memhere for applying frictional retarding force to the holder, a second membersupported on the first member for adjusting by its movement the value of saidforce, and reduction gearing supported upon the first said member and imparting to the second said member a movement positively coordinated with the movement of the coil holder. 7

4. An arrangement for controlling the tension on flexible material being withdrawn from aecoil comprising a rotary coil holder, means for applying a frictional retarding 'force to'the holder, a member for adjusting the value of said force, a pair of coaxial rotary driving members, one connected with the coil holder and the other with the-adjusting member and reduction gearing inserted I between and positively coordinating the movement of said coaxial members.

5. An arrangement for'controlling the tension on flexible material being withdrawn from a pair of coaxial coils, comprising a pair of coil holders, a separate friction brake acting one each of said holders, a spring exerting a force on each of said brakes, axially moving members adjusting the value of the force exerted by the springs, a screw threaded member and a nut acting directly on one of said axially moving members, reductlon gearingdriven by one of said coil lioldersand rotating the said nut, a second nut, a'rod passing through said coil holders and having a threaded portion on which works the second nut and connected at its other end to; the second axially moving member and coupling means between the two nuts by which the second is driven from the first and which permits relative axial movement of the two nuts.

ARTHUR SPENCER.

said shafts together, a worm wheel on one of i said shafts driven by the said worm and a In testimony whereof we aflix our signa- Line ies 

